2009 Volume 54 Issue 2 Pages 71-76
In order to establish an integrated weed control system for Italian ryegrass, which causes serious weed damage to wheat crops in Chuen area, Shizuoka, we conducted a field experiment and determined the effect of tillage and non-tillage treatments on the seedling emergence of the weed. The non-tillage of soil for soybean cropping resulted in an increase in Italian ryegrass emergence in the summer. In the subsequent wheat-cropping season, emergence did not decrease when compared to the emergence using the conventional tillage system. The lowest emergence was observed with a combination of tillage for soybean cropping and non-tillage for wheat cropping. For wheat cropping, the soil hardness was greater and the depth distribution of seeds that produced seedlings was shallower in the non-tilled soils than in the tilled soils. It is supposed that the combination of tillage for soybean cropping and non-tillage for wheat cropping is effective for the suppression of Italian ryegrass because the seeds of this weed are buried with tillage in the summer and the emergence is inhibited in the non-tilled and hardened heavy clay soil conditions in the winter.
